Broward County, Florida
Broward County, Florida—home to Ft. Lauderdale—is an urban coastal community that faces many environmental threats due to predicted climate change and variability over the next several decades, some of which are already beginning to be felt. Many of these threats are flood-related, and include sea level rise, an increase in the occurrence and magnitude of storm surge from tropical systems, an increase in the magnitude of tidal flooding due to elevated seas, and an increase in general flooding due to projected heavier rainfall rates. These flood threats are compounded by other geographic factors, including dense coastal development, low land elevations, a porous limestone substrate, and reliance on a complex network of canals for drainage and flood control.
In an effort to mitigate some of these impacts, Broward County’s Department of Environmental Protection and Growth Management is working directly with the U.S. Geological Survey in the development of a climate vulnerability and stormwater inundation model to assess the influence of changing climatic conditions and sea level rise on urban water resources and infrastructure.
Equipping Decision Makers with State-of-the-Art Tools
In order to visualize what the various flood threats may “look” like, and to assess how the modeled mitigation efforts may lessen these impacts, local decision makers, policy makers, scientists, planners, and other stakeholders need new and innovative tools that can facilitate better joint decision making. NEMAC developed 3D GIS-based visualizations of two project areas in Broward County to test the effectiveness of the use of this type of approach for communicating with decision makers.
Working directly with Broward County and Hazen and Sawyer, GIS datasets were collected and processed with 3D visualization programs, including Esri’s ArcScene, CityEngine, ArcGIS Pro, and ArcGIS Online. The datasets included high-resolution digital terrain models and aerial imagery. A key request was to make the 3D visualizations as realistic as possible. Therefore, NEMAC partnered with CyberCity 3D, Inc., to provide over 1,000 very detailed and highly accurate 3D building models. The 3D building models were then photo-textured by CyberCity 3D with oblique imagery from Pictometry that was made available through Broward County. These 3D building models, together with the terrain and imagery, formed the basis of the 3D visualizations. Additional elements were added as well, including streets, trees, and power lines, for added realism. Finally, flood overlays were added to “visualize” the flood impacts and to assess the USGS-modeled mitigation efforts.
Preliminary 3D Visualization Products
Animation showing 3D buildings with flood overlay
Animation showing how a 3D flood visualization is constructed
Buncombe County Multi-Hazard Risk Tool
The Buncombe County Multi-Hazard Risk Tool was developed by NEMAC to help emergency responders and planners prepare response and mitigation plans by providing information about the hazards that affect Buncombe County, the areas of the county that are affected by each hazard, the number of and total value of property parcels at risk from each hazard, and the key infrastructure and critical resources at risk during a hazard event.
Mapping Hazard Areas
The Risk Tool includes five important hazards in Buncombe County: flood, landslide, wildfire, dam failure, and winter storm. NEMAC created maps for each hazard by intersecting a map of property parcels with maps of hazard extents obtained from trusted sources, such as the North Carolina Department of Environment and Natural Resources, the Southern Group of State Foresters, and the North Carolina Floodplain Mapping Program.
Using ESRI server technology to serve datasets through the web, NEMAC developed the Risk Tool to help Emergency Operations Center staff update hazard mitigation plans more quickly and efficiently than before.
Creating Better Decisions
The Risk Tool helps provide information to the small towns and municipalities in Buncombe County, where planners do not have extensive in-house GIS resources. This helps foster well-informed decisions that affect entire communities.
A Valuable Resource
The Risk Tool facilitates online reporting and retrieval of geospatial information throughout the county and helps ensure a common base of geographic data available for hazard planning and response.
The Multi-Hazard Risk Tool uses data from a variety of trusted sources, including census data, recorded deeds, satellite and aerial photographs, and hazard layers generated by state geologists and hydrographers.
City of Asheville, North Carolina
Climate resilience is the ability of the natural, human, economic, and built systems to recover from and withstand impacts from weather and climate. Climate resilience planning is a way for communities to develop strategies for reducing their vulnerability to impacts from extreme weather events and climate change and to manage risk.
In 2016, the NEMAC team started working with the City of Asheville to guide staff through a five-step resilience planning process developed for the U.S. Climate Resilience Toolkit in a series of facilitated workshops. At the end of 2016 the team completed the assessment phase that highlights the primary climate-related threats the City faces. Currently, the team is identifying options to build resilience to the threats identified in the assessment phase.
Asheville has a history of climate-related impacts, including major flood events in 1916 and 2004, multiple landslides, and the record drought of 2007–2008. Communities and businesses, however, are not impacted solely by climate—they also face many non-climate stressors. These may include economic changes, land use issues, and the desire to preserve a sense of place. Asheville is experiencing some of these non-climate stressors, such as pressures from population growth and increasing demand for municipal services.
Building resilience involves consideration of both climate and non-climate factors.
The goal of the climate resilience planning project is to assist the City of Asheville in becoming more resilient in the face of existing hazards and environmental change. To that end, NEMAC led city staff through a series of six workshops between June and December, 2016, aligned with the Steps to Resilience set forth in the U.S. Climate Resilience Toolkit.
In Phase I of the project, over 25 participants representing 14 municipal departments worked through Steps One through Four of the resilience-building process as described below, and will continue to Step Five in 2017.
Step One: Explore Climate Threats
The main climate threats in Asheville are related to climate variability and extreme events, such as extreme precipitation, severe drought, and extreme heat. Recent events and past experiences help in understanding impacts, including flooding and runoff, landslides, water shortages and wildfire, and extreme heat. These impacts were assessed and documented in a thorough exposure analysis.
Step Two: Assess Vulnerability and Risks
Vulnerability is the susceptibility of societal assets and community services to impacts from existing or future threats. Vulnerability is made up of two main concepts: exposure and adaptive capacity. Both physical and socioeconomic conditions can influence a system’s resilience to the impacts from climate-related threats. This process included a vulnerability and risk scoping assessment for identified assets to specific climate threats.
Step Three: Investigate Options
Once vulnerable areas and assets were identified, options to build resilience were considered. Options were developed by brainstorming possible solutions and exploring what other groups have done in similar circumstances, and then were narrowed to a short list of actions that local stakeholders were willing to support.
Step Four: Prioritize Actions
After developing a list of 100 options, they were consolidated into actions and the important work of prioritization was begun. This prioritization process requires aligning limited resources to focus on the greatest risks, and involves discussing trade-offs with fellow stakeholders and determining the best way forward.
Step Five: Take Action (Implement)
The last step is implementing a plan. It is also important to monitor results and measure how effective the actions are.
The NEMAC team is currently working with the City of Asheville on the final stages of Step Four.
More information about the process and how the climate resilience work will be integrated with the City’s comprehensive plan can be found on the City’s project page.